Cold Test Results (~25°C Ambient Temperature)

For the testing of PSUs, we are using high precision electronic loads with a maximum power draw of 2700 Watts, a Rigol DS5042M 40 MHz oscilloscope, an Extech 380803 power analyzer, two high precision UNI-T UT-325 digital thermometers, an Extech HD600 SPL meter, a self-designed hotbox and various other bits and parts. For a thorough explanation of our testing methodology and more details on our equipment, please refer to our How We Test PSUs - 2014 Pipeline post.

The SeaSonic Focus GX-850 exhibits particularly high energy conversion efficiency for an 80Plus Gold unit, narrowly missing the 80Plus Platinum certification for an input voltage of 115 VAC due to a slight dip at maximum load. Its efficiency with an input voltage of 230 VAC is also very high for an 80Plus Gold-certified unit, with an average efficiency across the nominal loading range of 92%. The average efficiency drops to 90.1% if the input voltage is 115 VAC, a very significant 1.9% drop, yet it remains very high for an 80Plus Gold-certified product.

In its default setting on the SeaSonic Focus GX-850, the thermal control operates in a semi-fanless mode, which signifies that the fan activation is contingent on the requisite cooling demand. With the unit operating at room temperature, the fan activates when the load is greater than 240 Watts. This approach, while fostering quieter operation under low to moderate loads, leads to a relative elevation in the internal temperatures of the PSU prior to fan engagement. That, however, is virtually insignificant, as the fan engages long before the temperatures reach threatening figures.

As mentioned above, the SeaSonic Focus GX-850 has its fan remaining inactive until the load surpasses a defined wattage. Once activated, the fan operates at a virtually inaudible sound pressure level until the load extends beyond half the unit’s rated capacity. Beyond this load threshold, the thermal controller progressively augments the fan speed to adeptly manage the escalating cooling demands of the PSU, thereby ensuring a harmonious balance between operational efficiency, thermal management, and acoustic comfort.

Introduction, Examining Inside & Out Hot Test Results (~45°C Ambient Temperature)
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  • RomanPixel - Friday, December 1, 2023 - link

    I bought the MSI MPG Ai1000P from MicroCenter and it has the 12V-2x6 plug. Says so on the box and printed next to the plug on the unit it's self. The cable also has a yellow tip to indicate it's the 12V-2x6, came with a info slip of paper saying so. But MSI's website says it has the old connector. It's like a quiet revision.
  • Counterspeller - Wednesday, November 29, 2023 - link

    Been using Seasonic for years, have a 450W (don't remember the model) in my 10y old 4770, it's still working, used a TX-750 Platinum on my 1900x, using a TX-850 Titanium on this PC. Not 1 has failed.
  • Oxford Guy - Friday, December 1, 2023 - link

    I still have an ultra-cheap Xigmatek PSU from many many years ago that came with a 135mm FDB fan. The PSU still works, too. Why we're still getting 120mm fans in PSUs is beyond me.
  • 120or135 - Friday, December 8, 2023 - link

    is the fan really 120mm?
    says 135mm at their site

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